layui.use('form', function() {
	var form = layui.form;
    var $ =layui.jquery;
    var show_num = [];
    draw(show_num);

    $("#canvas").on('click',function(){
        draw(show_num);
    })

function getXmlHttp(){
    var xmlHttp;
    try{
        xmlHttp = new XMLHttpRequest();
    }catch(e){
        try{
            xmlHttp= new ActiveXObject("Msxml2.XMLHTTP");
        }catch(e){
            try{
                xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
            }catch(e){
            }
        }
    }
    return xmlHttp;

}


document.getElementById("mybu").onclick = function() {
   var username = document.getElementById("LAY-user-login-username").value;
   var password = document.getElementById("LAY-user-login-password").value;
   var code = $("#LAY-user-login-vercode").val();
   if (username==="" ||password===""){
       layer.msg('请输入账号和密码',{
           icon:2,
           time:2000
       })
       return false;
   }

    if (code===""){
        layer.msg('请输入验证码',{
            icon:2,
            time:2000
        })
        return false;
    }

    if (code!==show_num.join("")){
        layer.msg('验证码错误',{
            icon:2,
            time:2000
        })
        draw(show_num);
        return false;
    }
   var request = getXmlHttp();

    request.open("POST","/login",true);
    request.setRequestHeader("Content-type","application/x-www-form-urlencoded");
    request.send("username="+username+"&password="+password);
    request.onreadystatechange=function()
    {
        if (request.readyState==4 && request.status==200)
        {
            var  message=request.responseText;

            layer.msg(message);
            if(message==="success"){
                layer.msg('登入成功', {
                    icon: 1,
                    time: 2000
                }, function() {
                    location.href = "/main";
                });
			}else {
                layer.msg('账号或密码错误', {
                    icon: 2,
                    time: 2000
                });
			}
        }
    }


	return false;
}

function draw(show_num) {
        var canvas_width=130;
        var canvas_height=35;
        var canvas = document.getElementById("canvas");//获取到canvas的对象，演员
        var context = canvas.getContext("2d");//获取到canvas画图的环境，演员表演的舞台
        canvas.width = canvas_width;
        canvas.height = canvas_height;
        var sCode = "A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0";
        var aCode = sCode.split(",");
        var aLength = aCode.length;//获取到数组的长度

        for (var i = 0; i <= 3; i++) {
            var j = Math.floor(Math.random() * aLength);//获取到随机的索引值
            var deg = Math.random() * 30 * Math.PI / 180;//产生0~30之间的随机弧度
            var txt = aCode[j];//得到随机的一个内容
            show_num[i] = txt.toLowerCase();
            var x = 10 + i * 30;//文字在canvas上的x坐标
            var y = 20 + Math.random() * 8;//文字在canvas上的y坐标
            context.font = "bold 23px 微软雅黑";

            context.translate(x, y);
            context.rotate(deg);

            context.fillStyle = randomColor();
            context.fillText(txt, 0, 0);

            context.rotate(-deg);
            context.translate(-x, -y);
        }
        for (var i = 0; i <= 7; i++) { //验证码上显示线条
            context.strokeStyle = randomColor();
            context.beginPath();
            context.moveTo(Math.random() * canvas_width, Math.random() * canvas_height);
            context.lineTo(Math.random() * canvas_width, Math.random() * canvas_height);
            context.stroke();
        }
        for (var i = 0; i <= 30; i++) { //验证码上显示小点
            context.strokeStyle = randomColor();
            context.beginPath();
            var x = Math.random() * canvas_width;
            var y = Math.random() * canvas_height;
            context.moveTo(x, y);
            context.lineTo(x + 1, y + 1);
            context.stroke();
        }
    }

    function randomColor() {//得到随机的颜色值
        var r = Math.floor(Math.random() * 256);
        var g = Math.floor(Math.random() * 256);
        var b = Math.floor(Math.random() * 256);
        return "rgb(" + r + "," + g + "," + b + ")";
    }

});